Current Network-Based back up and restore systems are primarily tape-based, where a number of generations exist:
Stand alone backup and restore systems, with a tape device attached directly to a computer.
Server and LAN based backup and restore systems: where the data is being moved from storage to tape via the server and the LAN.
LAN-free backup and restore systems: move the data over the SAN to the tape.
Early disk-based backup and restore systems are used for buffering the data on a dedicated disk before it moves into tapes. These systems are sometimes called tape emulation or virtual tape.
LAN- and Server-free backup and restore systems, which use a third-party Data Mover to copy backup data over the SAN.
Disk-based backup and restore systems, the latest generation, which practically does not exist yet.
U.S. Pat. No. 5,664,186 to Bennet et al. teaches a file management and backup system operating in file format, whereas the present application is not limited thereto but operates in either one of both file format and block format.